Arrma offer many keenly priced, quality cars, but their best work is saved for halo models such as this. The Senton 6S BLX is a not-safe-for-kids, balls out, bash-proof powerhouse of a truck. We are talking a Traxxas Slash style short course truck but faster, with more power and yet for substantially less money! So lets unbox the Senton 6S BLX and put Arrma's top speed claim to the test.
The Senton 6S BLX at a glance
Factory uprated short course RC truck
Powerful BLX 2050kV brushless motor
150Amp BLX185 brushless ESC
Strong 15kg metal gear steering servo
Adjustable oil-filled shocks
Upgraded servo mounts, bulkheads, braces and shock towers
Tactic TTX300 2.4GHz 3-channel radio system
dBoots Sidewinder tyres on large multispoke wheels
56cm long, 30cm wide and 20cm tall with a weight of 3.8kg without batteries (!)
What's in the box?
Included in the box is the ready-to-run truck, transmitter, shock spacers, 16T high-speed pinion, tools, manuals and a pair of XT90 battery connectors.
Including several allen keys, socket drivers and a detailed printed manual (featuring extensive exploded diagrams) is really helpful for adjusting or repairing the vehicle.
Heavy Duty Chassis
As promised the truck is built tough. A thick metal chassis plate holds the drive-train components and electronics. Cage-stylised plastic tube structures sit at the ends, sides and roof, maintaining the shell shape in crashes or rolls.
Materials have been carefully selected for a balance of strength and weight, with tough plastic employed for the lower and upper suspension arms. Adjustable oil filled shocks have big 4mm shafts and mount to aluminium shock towers front and rear. Red anodised bulkhead and suspension reinforcement components add some bling to the otherwise matt black finish.
Thick metal driveshafts feed oversized hubs (look how little clearance there is to the rim in the below photos) that are in turn mounted to the arms with large metal ball joints. The steering system features dampers and a large servo-saver mated to the metal servo horn via a linkage.
Metal propshafts link the three open differentials that drive the truck along, the centre diff featuring a big 50T spur gear. Its great to see metal used so extensively throughout the drivetrain giving us confidence in its longevity.
Powerful Electronics
The 'business end' of the truck is sat on the right hand side of the chassis plate. At the back the beefy 2050kv 4-pole brushless motor is fixed into an anodised plate, sat alongside the central diff.
Sat in-front of that is the Arrma BLX185 brushless speed controller, reportedly a lightly altered Hobbywing Quickrun 150 ESC. It retains the fan, remote power switch (though sadly inaccessible with the body in place) thick power cables and 150A support, if not all the programming options of the original.
Lastly up front we have the bright red 15kg, ADS-15M metal gear steering servo, mounted to its own hard plastic cage and linking to the steering system via a metal servo horn. Overall the electronic choices look really promising with waterproofing present at the essential points.
Short Course body
The included short course body has a matte finish to the paint. The black and green livery is contrasted with bright red 6S stickers and the usual selection of light/exhaust/opaque window detail stickers. We aren't completely sold on the brutish style of the truck but it certainly looks like it means business.
The body pins are tethered to the shell via rubber straps which whilst ugly, make fitting and removing it a breeze. Vents are cut into the bonnet/hood section with further cutouts in the rear deck, potentially to lower the air pressure under the shell and keep it pressed down at high speed. Cutouts at the front and rear allow the big tubular bumpers to poke through and save the body from impacts.
Underneath the body has been reinforced with tape on areas where the chassis and tyres will likely rub, you can see this and the aforementioned vents in the photos below.
Opinions are split on the (removable) embossed, clear rear spoiler. Its clearly needed to keep the rear planted when driving at high speeds (as we found once, almost doubling up as a wheelie bar) but not all of us like the transparent aesthetic.
Tactic Transmitter and Reciever
The included Tactic TTX300 2.4GHz 3-channel radio does the job. The foam covered steering wheel is comfortable in use and we had no issues with range or dropouts. Probably the most important element of this transmitter is the steering rate dual rate adjustment. Combining a 'dumb' ESC with 6S power is often a recipe for disaster, leaving your fishtailing down a loose dirt track.
You only have to look at how even moderately powerful Traxxas models get fitted out with their TSM (Traxxas Stability Management) receivers, to get an idea of the difficulties of driving a RWD truck with this much power and no extra assistance (as this model has)! In short you are going to be glad for the ability to wind that in to maintain steering control at speed.
On the truck the receiver is hidden away in a small waterproof box in-front of the battery tray.
What batteries and charger would you recommend?
If you are competent at soldering, Arrma do include two XT90 connectors in the package. This means you can either re-purpose batteries you already have, or buy two competitively priced, high burst rate 3S cells and re-terminate them. Because we are lazy, we opted for these 5000mAh 3S Overlander Supersport Pro LiPo batteries that ship with the requisite terminations in place. At 138 x 42 x 27mm two can stack comfortably in the max dimensions of the 158 x 70 x 48mm battery tray.
Whilst the ESC will accept the 22.8v of 6S power, its worth noting that it will run on smaller cells. Arrma also include a small bridging plug allowing you to cap off one of the battery terminals and run the model on a single 4S LiPo.
Stacking the big cells into the battery tray can actually be quite fiddly to ensure enough cable length for connection. Below you can see the orientation we opted for, first for a single battery and below that two.
We found placing the lower battery with its lead out of the 'rear', then the one on top with the lead out of the 'front' (poking through the gap in the sliding tray cap) worked best, allowing the connectors to reach both ends of the ESC wiring (securing it under that central clip) and the balance leads to be tucked away with the supplied hook-and-loop straps.
The XT90 batteries cause a further headache when it comes to charging, as even the higher end chargers often lack this connector as an option. As such we now stock a XT90 to 4mm banana plug charging lead specifically for this.
Driving the Senton
At the pump track the Senton 6S is immense fun. It has a brushless 'Slash' feel to it, in the rabid way it tears around. There really is so much power on tap and when it grips it certainly goes. Out of the box this truck truly puts a smile on your face.
At 55cm long the truck feels more like a 1/8th scale model than a 1/10th. For something of this size and weight to get-up-and-go so readily is pretty crazy.
Despite the open differentials, there is definitely feels a rear bias to the drive, allowing you to pull off incredible power-slides whenever the surface gets a little loose. The oil filled diffs can be rebuilt with differing viscosity oils to alter handling dynamics if this isn't your style.
In the air it has great balance, allowing you to jump doubles with confidence. Despite its fairly weighty chassis (especially with two batteries in it) it is capable of incredible hang time. Hit the gas on the ramp takeoff and the resulting hang-time is ludicrous, just check out some of these photos.
As such we are glad that its 'built tough'. Should you missjudge it, the shocks can withstand a big, hard landing. Indeed the truck will shrug off some big falls or long cartwheels.
We hammered the car through several packs and none of the arms, or dampers gave up. The truck itself is now filthy but incredibly still in one piece. However if you really get a landing wrong there is only so much a damper or a servo saver can do!
Yes, we destroyed the servo on the first outing at the pump track. This isn't unusual when abusing hobby-grade RC but we were a little disappointed at this price point. We replaced it with a with a Savox 20kg Coreless Titanium Gear Servo and haven't had any issues since.
Beyond servo issues, we were not that taken by the Dboots tyres. Glued to the rims we had no issues with them ejecting, but the tread pattern (whilst looking rad) didn't favour our surface choice of loose dirt at the pump track. They performed a lot better on subsequent runs on hard packed dirt and tarmac but we feel short course trucks should be at home on the soft loose dirt just like their full size counterparts.
Thus if we were going to change anything we'd probably switch out the wheels and tyres for something from proline. The wheel hubs are 17mm in size so there are plenty of aftermarket options available. We'd also consider some sort of anti roll bar to resist the body roll moment as it does enjoy popping up onto two wheels.
This is not a truck for driving slowly, due to either the programming of the ESC or the cogging of the motor there is a slight dead-zone in the throttle channel meaning it leaps into the power as opposed to smoothly accelerating from stationary.
Despite the power (and the comparatively hot temperatures it was tested in) we had no overheating issues, so those body vents potentially do double duty for cooling.
Just how quick is it out of the box?
Many of our browsing customers seem preoccupied with the top speed of their potential purchase. We prefer models with a good balance of power and control, finding little entertainment in 'drag car' RC models, powering along in a straight line for a few seconds.
That said, feeding a 2050kV brushless motor with over 22volts, we had to see what this truck was capable of, right out of the box. We stuck a GPS enabled GoPro (an simple and robust way to get a speed readout with a nice speedo overlay) to the roof of the truck and attempted several high speed runs up and down our private carpark one evening :
We recommend only trying this in a controlled environment with the dual rate down to around 15% to avoid any sudden, sharp, truck flipping turns! As you can see, on tarmac the truck has blistering acceleration, its motor screaming as it powers the Senton up to 52mph in a matter of seconds.
Setting our sights on 60mph
Few would argue that 52mph is slow for a model this size, yet Arrma provide an additional pinion gear along with a product card suggesting that 60+mph is possible, so naturally we had to put it to the test!
First up, fitting the 16T pinion gear. Despite the exposed nature of the drivetrain, working on the truck isn't the easiest. We opted to remove the ESC, the ESC baseplate (held into the floorpan by numerous screws) and some of the central body support rollcage to get enough access to work on the pinon area.
On our unit it appears that the factory went OTT with the red loctite holding the pinion of stock 14 tooth pinion onto the motor shaft. After removing the grub screw we failed to lever the pinion over the lipped end of the motor shaft. Having attempted all manner of levers we gave up and heated the spur gear up with a heat gun before it finally popped off.
With the new pinion fitted you have to bring the power in progressively or the front end will lift, leaving you with zero steering control. As you can see from the earlier photo, the rear wing has a chunk missing from the end having doubled up as a wheelie bar a few times. Our initial tests with the GoPro had it mounted on the front of the car as seen above, but as struggled to improve on several runs we decided to move it to the rear of the body concerned that it was hampering the aerodynamics. With this setup we could reliably hit 59mph, just shy of the target.
We feel the manufacturers claim of 60mph on this gearing is pretty ambitious, although factors such as air temperature/humidity, surface traction, battery temperature probably had an effect; That or our GPS speedo just isn't that accurate! If you really do need the data to back up those pub-chat claims we recommend picking up a 17 Tooth Mod-O pinion which should comfortably clear it with this motor.
What are the alternatives?
If you cannot stretch to this balls-out 6S BLX model, Arrma do offer a (much) slower brushed version of the truck in a red/black or blue/black body. Whilst the dimensions and underlying bodyshell are similar, the model naturally lacks the power and upgraded components of the high end BLX powered truck reviewed here.
The current market favourite is Traxxas' Slash, available in brushed as well as brushless and even brushless pro variants. They are fantastic trucks with similar levels of build quality and performance, albeit at a higher comparative price when comparing apples to apples.
Along the short-course truck theme you could consider the HPI Blitz, Maverick Strada SC, or the ECX Torment. All are basic brushed models with a similar aesthetic, varying prices and a performance level perhaps more suitable for children.
If you like the idea of all this power but aren't fond of the looks, consider the Arrma Typhon, a 1/8th 4WD scale model running much of the same drivetrain but with a buggy chassis and body, all for around £50 less.
If you are looking for more RC model reviews you are in the right place, we have plenty of tests featuring some of the greatest trucks on the market today. Check our reviews category on this blog site for more!
Written by
Tom Begley
Keep up-to-date with the world of gadgets, drones and cars
